Lecture 8. Proteins

Question 1

Function of green fluorescent protein

Answer 1

Acts as a biosensor or cell marker. Used to study protein reactions and visualise promoter activity

Question 2

What is a ligand ?

Answer 2

Molecule bound reversibly to a protein

Question 3

What are two examples of ligands ?

Answer 3

1. alpha 1

2. antitripson

Question 4

What is a porphyrin ring composed of ?

Answer 4

4 pyrrole rings

Question 5

What type of protein is a myoglobin ?

Answer 5

A storage protein

Question 6

What type of protein is a hemoglobin ?

Answer 6

A transport protein

Question 7

How many coronation site of iron is there ?

Answer 7

6

Question 8

Where are the 6 coronation sites of iron ?

Answer 8

4 in plane of portoporphrin

2 in perpendicular to plane

Question 9

What is fractional saturation ?

Answer 9

Fraction of the total binding sites occupied by dioxygen ligand

Question 10

What does hemoglobin consist of ?

Answer 10

Consists of four myoglobin like subunits (two alpha and two beta chains)

Question 11

Structural characteristics of hemoglobin

Answer 11

1. all alpha helix
2. very homologous
3. tetrameric - quaternary structure

Question 12

What is the benefit of cooperativity ?

Answer 12

Permits a more sensitive response to ligand concentration